Research in cognitive neuroscience utilizing infant monkeys and human adults suffering from temporal lobe damage has suggested that visual recognition memory is mediated by the same limbic structures that support other forms of explicit or declarative memory. Unfortunately, the behavioral procedures typically used to study recognition memory in the human infant do not lend themselves to an explication of the neural processes or structures that underlie such memory. In addition, the anatomical/lesion method used with non-human primates and neurologically compromised human adults does not permit an examination of the neural transactions that transpire during recognition memory; this method also does not lend itself to the study of the normal young of our species. In order to examine the neurophysiological processes that underlie the development of recognition memory, and to relate these processes to overt behavior, approaches other than those used thus far must be employed. To this end a series of studies is being proposed with human infants that will involved recording event-related potentials from the scalp. An overt behavioral measure (looking time) will also be recorded, permitting us to relate our electrophysiological data to the overt (behavioral) expression of memory. The specific issues to be addressed in this proposal concern a) the neural processes that underlie visual recognition memory, b) the link between the behavioral and physiological expression of recognition memory, c) changes in the physiological and behavioral expression of visual recognition memory over the first year of life, and d) to a very limited degree, the anatomical locus of visual recognition memory as inferred from its electrophysiological expression. Finally, to assist in interpreting the functional significance of the obtained results, a series of parallel studies will also be conducted with adults.